Code for session problems

More solutions will be added soon...

Note: Please attempt problems before looking at the solution!

(or spend at least 30 minutes thinking about the solution)

Resources (more in-depth topics / problems):

Assiut Training Sheet: https://codeforces.com/group/MWSDmqGsZm/contests
Mostafa Saad's Sheet: https://codeforces.com/blog/entry/65133
CSES: https://cses.fi/
USACO: http://usaco.guide/
AtCoder: https://kenkoooo.com/atcoder/#/list/